The overall goal for this project is to design a compact cryocooling device for fast, reproducible and reliable cryopreservation of protein and virus crystals for X-ray cryocrystallography. X-ray crystallography is the most powerful and widely used tool for determining the molecular structure of proteins, viruses, nucleic acids and biomolecular complexes. Flash-cooling crystals in liquid nitrogen and collecting data at T=100 K simplifies storage, transport and handling, and dramatically increases the amount of X-ray data that can be obtained from each crystal. However, the cooling process itself damages crystals. Many important targets including viruses, membrane proteins and biomolecular complexes can be very difficult to successfully cool. Moreover, current cooling methodologies, which are time-consuming and done by hand, lead to large variability in cooling outcomes and diffraction quality. The proposed device will provide reliable and reproducible cooling at rates up to 100 times greater than in current best practice. This will eliminate crystalline ice formation during cooling and dramatically reduce required cryoprotectant concentrations. This project will focus on designing the device, developing a commercial prototype, evaluating the performance of prototype. PUBLIC HEALTH RELEVANCE: This project will benefit public health by developing an improved method of conducting X-ray Cryocrystallography. This technique is vital for basic biomedical research and improving its accuracy and efficacy will have broad-scale impacts on developing new drugs and treatments for diseases.